Japanese soy sauce tends to contain more wheat than Chinese soy sauce, giving Japanese soy sauce a slightly sweeter taste.

Soy sauce contains a small amount of naturally occurring MSG. It can also be extremely salty.

Soy sauce is shelf-stable because it contains added salt, alcohol, or sodium benzoate. Since alcohol quickly boils off when stir-frying (a typical use of soy sauce), an alcohol-based soy sauce is preferable when using copious amounts.